The present invention relates to a method for controlling a vehicle, operation of a control element by the driver of the vehicle being sensed, and the steering angle of the vehicle being regulated depending on the operation of the control element.
The present invention relates primarily to a working machine in the form of a wheel loader. The wheel loader comprises (includes, but is not necessarily limited to) a front and a rear body part that are interconnected in an articulated manner and each has a drive axle. The body parts are pivotable and/or rotatable relative to one another around an articulation point via two hydraulic cylinders arranged between the two parts. In this regard, the terminology “steering angle” is utilized herein to denote mutual adjustment of the two drive axles. The hydraulic cylinders are therefore arranged for steering (turning) the wheel loader.
A wheel loader usually has normal steering-wheel steering, but may in parallel be equipped with lever steering. Using the steering-wheel steering, the driver regulates mechanically a first hydraulic valve which in turn transmits hydraulic energy to the hydraulic cylinders. When lever steering is used, hydraulic energy is instead transmitted to the hydraulic cylinders via a second hydraulic valve. This second hydraulic valve, however, is controlled by electric signals so that when the lever is moved, an electric signal is generated that controls the second hydraulic valve.
When lever steering is used, the speed of change of the steering angle is controlled by the position of the lever. A large lever deflection gives a rapid change of steering angle, and a small lever deflection gives a slow change of steering angle. When the lever is guided back into the neutral position after a deflection, the steering angle which has been brought about is maintained.
The steering wheel is usually used for transport, and the lever is usually used for work at lower speeds such as, for example, loading a truck, in order to increase driver comfort. In some applications, however, the driver may prefer to use the lever for transport as well. Transport and loading are two different handling operations of the wheel loader which place very different demands on the vehicle. During a loader cycle, the wheel loader is driven forward and backward for short distances and is turned in the meantime in order to load and unload the bucket.